At 7:36 PM 3/31/96, Mike Duvos wrote:
We aren't talking about IC masks here. We are talking about electrostatic charges which would instantly leak away if the insulation around them were in the least bit compromised.
The surface layers above the active portion of a chip can be stripped away and chip remains functional. This includes the outer packaging layers (epoxy, or of course, ceramic with metal lids) and parts of the so-called "scratch protection," usually a type of silicate glass. The active capacitors are not affected by removal of these layers.
Such data wouldn't even survive the preparation for scanning microscopy, much less the actual inspection process.
Actually, we did it all the time in my lab at Intel, and I understand from my former co-workers that the technology has only gotten better. (This does not mean voltage contrast is easy. For one thing, modern chips have 3-5 metal layers, due to spectacular advances in chem-mechanical polishing, and each metal layer acts as a ground plane shielding the lower layers from visibility and inspection with electron beams. And EPROM and EEPROM cells are effectively impossible to analyze, for various reasons.) This does not mean I think reverse-engineering of smart cards or satellite boxes is easy. SQUIDs won't do it, either. --Tim May Boycott "Big Brother Inside" software! We got computers, we're tapping phone lines, we know that that ain't allowed. ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay@got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero W.A.S.T.E.: Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 - 1 | black markets, collapse of governments. "National borders aren't even speed bumps on the information superhighway."